How to use the @fortawesome/free-brands-svg-icons/faFacebook.faFacebook function in @fortawesome/free-brands-svg-icons

/* eslint-disable no-console */
const colors = require('colors/safe');
const fs = require('fs');

const fontawesome = require('@fortawesome/fontawesome-svg-core');
const faAt = require('@fortawesome/free-solid-svg-icons/faAt').faAt;
const faComments = require('@fortawesome/free-solid-svg-icons/faComments').faComments;
const faDiscord = require('@fortawesome/free-brands-svg-icons/faDiscord').faDiscord;
const faDiscourse = require('@fortawesome/free-brands-svg-icons/faDiscourse').faDiscourse;
const faFacebook = require('@fortawesome/free-brands-svg-icons/faFacebook').faFacebook;
const faKeyboard = require('@fortawesome/free-solid-svg-icons/faKeyboard').faKeyboard;
const faMeetup = require('@fortawesome/free-brands-svg-icons/faMeetup').faMeetup;
const faReddit = require('@fortawesome/free-brands-svg-icons/faReddit').faReddit;
const faSlack = require('@fortawesome/free-brands-svg-icons/faSlack').faSlack;
const faTelegram = require('@fortawesome/free-brands-svg-icons/faTelegram').faTelegram;
const faTwitter = require('@fortawesome/free-brands-svg-icons/faTwitter').faTwitter;
const faUsers = require('@fortawesome/free-solid-svg-icons/faUsers').faUsers;

buildAll();

function buildAll() {
    var iconMap = {
        discord: faDiscord,
        discourse: faDiscourse,
        facebook: faFacebook,
        forum: faComments,